Stupid Question from a novice...

[hoosier daddy]

This may be a stupid question but because I'm new to the furnace situation I will ask any way.

I have a indoor hot air furnace and because it's not cold enough to run the thing very hot and stay in the house I am finding low stack temps at different points of the day-night. The stack temp will drop below 200 on the down side of a burn...ie 6 or 7 hours in. I have a really nice bed of coals sitting in the bottom of the furnace but because the thermostat is not calling for heat the induction motor is not running and because I don't need large amounts of heat I have the furnace damped down.

When I put fresh wood in I can open the door or the draft and easily get the temp back to 350 to 500 range quickly and maintain 400 for most of the burn. My question is really...havent I already burnt all of the moisture out of the wood when I have a bed of coals...??? so is the low stack temp an issue at this point? I am planning on taking the stack apart (not a big job) after a solid month of burning and checking it out but I don't want to find out too late that I'm creating some kind of dangerous situation...

The wood I am burning is seasoned cherry, ash, walnut and a little silver maple. it's all dry. Most of the time you cant even see smoke, exception is when you first throw new wood in, but once you get stack to 300+ smoke disapears...

thanks in advance for the comments.

 

[pook]

http://www.msuextension.org/search/...&cof=FORID:11&q=wood+combustion&sa.x=0&sa.y=0 no smoke= minimal creo in chimni. got a CO detector? though CO is odorless i think U can smell a leaky woodstove unlike a gas appliance

 

[cre73]

If your not seeing smoke except at reloads and your wood is seasoned as you say the low stack temps should not be an issue. I know my stack temperatures fluctuate through my loading cycles especially this time of year and I have never had more than a cup or two of build up when I cleaned my chimney.

 

[1harlowr]

Low temp burns give off more smoke than high temp burns. The low temp = incomplete combustion. High temps = more complete combustion....assuming both using the same wood

 

[Mike PA]

I don't think the low stack temps at the end of a burn are as critical as in the beginning, as coals tend to produce little smoke (all of the volatile components of wood have already been off-gassed). If you want a new woodstove go through the burn cycle, your secondary burn cycle does not last throughout the course of the fire, assuming more wood is not added. Take a peak at your chimney when the stack temps are lower and see what comes out. Chances are, you would have very little smoke, thereby producing very little creosote, if any.